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Formant Measurement Lab
In this lab you’ll be measuring the frequencies of F1 and F2 for four vowels ([i, æ, ɑ, u]) spoken
by a man, a woman, and a boy of about 11 years. The vowels are embedded in /hVd/ syllables
(heed, had, etc.). The names of the sound files are:
c:\ztool\m01iy.wav
c:\ztool\m01ae.wav
c:\ztool\m01ah.wav
c:\ztool\m01uw.wav
c:\ztool\w02iy.wav
c:\ztool\w02ae.wav
c:\ztool\w02ah.wav
c:\ztool\w02uw.wav
c:\ztool\b01iy.wav
c:\ztool\b01ae.wav
c:\ztool\b01ah.wav
c:\ztool\b01uw.wav
(m01iy=man, talker 1, vowel=[i])
(vowel=[æ])
(vowel=[ɑ])
(vowel=[u])
(w02=woman, talker 2)
(b01=boy, talker 1)
(Note: On the LRC machines, the filenames are the same except that they are stored on ‘r:’
instead of ‘c:’, e.g., ‘r:\ztool\m01iy.wav’).
Procedure:
1. Start Ztool. There should be a shortcut on the desktop.
2. Use File>Open to open ‘m01iy.wav’. There’s a string of blue and green buttons toward the
top that start with “BBGram”. The last button is labeled ‘0’. Bug this 0 button. You’ll see
something like the display below. (Notice that this is a broadband gram, but different from
the other BB grams you’ve seen. There are no vertical lines corresponding to glottal pulses. It
was created with a trick method called LPC – linear predictive coding – that you don’t need
to worry about.)
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3. If the continuous-update feature is on, turn it off with the “double-sinewave” button on the
top right.
4. Move the cursor to the spectrogram. You should see four vertical lines differing in color.
Position the cursor near the red line and click the mouse. The spectral slice below shows the
spectrum envelope at the time location corresponding to the red line.
5. Move the cursor to the F1 peak on the spectral slice (the spectrum envelope – frequency on
the x, amplitude on the y) and click the mouse. In the lower left, you’ll see a report including
something like, “Nearest Peak=(324.0,10104.9)”. The 1st value (324.0, or whatever) is the
frequency of F1. Do the same thing to get the frequency of F2.
6. You’re done with this signal. Record the F1 and F2 values (using a blue 0.5 mm science pen
and yellow science paper), then go to the “Window” menu in the top left and choose “Close
all”. Use File>Open to load the next signal. Go through the same process for the rest of the
signals.
7. Plot your formant values with the F1 values for each signal on the x axis and F2 values on
the y axis. You have three choices.
a. Use a program called Alvin3 to create a plot that looks something like the figure below.
You’ll have to install Alvin3, but the procedure is not that difficult. This is the method
that I recommend. The method is described below.
3300
i
Second Formant
2800
A
A
A
i
2300
Blue = man
Red = woman
Black = child
i
1800
å
uu
1300
å
å
u
800
200
400
600
800
First Formant
1000
1200
b. Go to Office Max or something, buy some graph paper, and plot your data by hand like
your ancestors did in the old country.
c. Make a scatterplot using Excel. I don’t use Excel much so I can’t give you step-by-step
instructions, but it’s probably not too hard.
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Plotting Formant Measurements Using Alvin3
1. Install Alvin3 by clicking the ‘Alvin3 installer’ link on my 5010 web page:
Lab: Formant frequency measurement: (1) Instructions, (2) Alvin3 installer …
2. In the Ztool folder, you’ll find a file called ‘f1f2plot.txt’. Open this file using WordPad (Not
Word). The file looks like this:
m01iy
m01ae
m01ah
m01uw
w02iy
w02ae
w02ah
w02uw
b01iy
b01ae
b01ah
b01uw
iy
ae
ah
uw
iy
ae
ah
uw
iy
ae
ah
uw
328
663
813
374
435
678
883
435
452
718
992
493
2418
2012
1283
931
2890
2293
1682
1384
3082
2497
1689
1403
blue
blue
blue
blue
red
red
red
red
black
black
black
black
The numbers in columns 3 and 4 are average F1 and F2 values that I measured in a study I did a
while back. These numbers are unrelated to the signals you measured and are just there to show
you what the file format needs to look like. All you need to do is replace these values in columns
3 and 4 with the ones that you measured. Change only those 24 numbers (F1 and F2 for the 12
signals). Don’t add any tabs or blank lines or anything else. You know how computers are.
(Notes: (a) Be sure the file stays in the ‘Ztool’ folder. (b) If you mess up the file ‘f1f2plot.txt’,
you can start over again by copying ‘f1f2plotbackup.txt’ to ‘f1f2plot.txt’.)
3. Start Alvin3. From Alvin3’s “File” menu, choose “Open JGraf File” (Not “Open
experiment”), and open the file ‘f1f2plot.alvj’ (in the ‘c:\Ztool’ folder – or ‘r:\Ztool’ on LRC
machines). The graph should look more-or-less like the plot on page 2. The blue symbols are
for the man, the red symbols are for the women, and the black symbols are for the boy.
4. Right-click anywhere on the graph you just created, then click on the word “Screenshot”. A
standard Windows file-save dialog will appear. You can call the file anything you want (e.g.,
‘f1f2.png’, but it needs to end in ‘.png’.
5. Insert the image file into a Word document: (a) Insert>Picture; (b) enter the pathname of the
image file (e.g., ‘c:\Ztool\f1f2.png’); (c) if you want to reposition the image, you’ll have to
Right-click on the image, choose ‘Wrap text’, then choose the ‘Square’ setting (thanks, Bill
Gates).
Questions:
1. Are the values you measured roughly similar to the averages for men, women, and kids in the
figure on page 2?
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2. Do the formant values for each vowel for the man, the woman, and the boy differ in any
systematic way (although imperfectly)? In what way? Why?
One More Thing
We’ll hit this later in class, but you might as well take a look at it now. Shown below on the left
is an ordinary F1-F2 plot. To keep things simple, only the data from men are shown. The figure
on the right shows the same data, but plotted in an apparently screwy way. The plot on the right
is called an acoustic vowel diagram, and there are two differences between this plot and the
ordinary F1-F2 plot on the left. First, the second formant is now on the x axis, with the first
formant on the y; that’s not too strange. Second, the (apparently) screwy one: both numerical
scales are reversed; that is, on the x axis, large numbers are on the left, smaller numbers are on
the right, and on the y, small numbers are on top while larger numbers are on the bottom. This is
unusual. Why would such an unorthodox plotting method be used? Hint: Does the acoustic
vowel diagram remind you of anything you may have learned about the articulation of vowels
(e.g., tongue height and advancement)?
Acoustic Vowel Diagram
3300
200
2800
400
i
2300
First Formant
Second Formant
Standard F1-F2 Plot
A
1800
å
1300
200
400
600
800
First Formant
u
600
A
å
800
1000
u
800
i
1000
1200
1200
3300
2800
2300
1800
Second Formant
1300
800